Bound-electron–positron pair production in relativistic heavy-ion collisions

Abstract
Previously reported large nonperturbative enhancements of bound-electron–positron pair production in heavy-ion reactions are shown to be extremely gauge dependent due to incompleteness of the basis set. Large-basis calculations for the Pb on Pb system put a probable upper limit of the order of 10 b on the correction to perturbative calculations of the K-orbit-electron–positron pair production at ultrarelativistic heavy-ion colliders such as RHIC; this is to be added to the perturbative value of about 115 b.